1. Protists

2. If the mitochondria and chloroplasts in eukaryotic cells resulted from endosymbiosis, what features might we expect these organelles to contain?
a plasma membrane, DNA, and ribosomes
a plasma membrane, nucleus, and ribosomes
nucleus, DNA, and ribosomes
a plasma membrane, nucleus, and cilia
nucleus, ribosomes, and cilia
Answer: a 2

3. If the mitochondria and chloroplasts in eukaryotic cells resulted from endosymbiosis, what features might we expect these organelles to contain?
a plasma membrane, DNA, and ribosomes
a plasma membrane, nucleus, and ribosomes
nucleus, DNA, and ribosomes
a plasma membrane, nucleus, and cilia
nucleus, ribosomes, and cilia 3

4. Which of the following statements about slime molds is correct?
Cellular slime molds have haploid zygotes.
Cytoplasmic streaming helps distribute nutrients and oxygen in cellular slime molds.
In plasmodial slime molds, the haploid condition is the dominant part of the life cycle.
Cellular slime molds have fruiting bodies that function in sexual reproduction.
Cellular slime molds form masses when food is scarce, but their cells remain separated.
Answer: e 4

5. Which of the following statements about slime molds is correct?
Cellular slime molds have haploid zygotes.
Cytoplasmic streaming helps distribute nutrients and oxygen in cellular slime molds.
In plasmodial slime molds, the haploid condition is the dominant part of the life cycle.
Cellular slime molds have fruiting bodies that function in sexual reproduction.
Cellular slime molds form masses when food is scarce, but their cells remain separated. 5

6. The largest group of eukaryotic organisms is the
vertebrates.
animals.
plants.
protists.
fungi.
Answer: d 6

7. The largest group of eukaryotic organisms is the
vertebrates.
animals.
plants.
protists.
fungi. 7

8. Photosynthetic eukaryotes contain both mitochondria and chloroplasts
Photosynthetic eukaryotes contain both mitochondria and chloroplasts. Which sequence most likely describes the evolution of this group?
Ancestral anaerobic prokaryote engulfs heterotrophic prokaryote and then engulfs photosynthetic prokaryote.
Ancestral anaerobic prokaryote engulfs photosynthetic prokaryote and then engulfs heterotrophic prokaryote.
Both sequences are equally likely.
Answer: a 8

9. Photosynthetic eukaryotes contain both mitochondria and chloroplasts
Photosynthetic eukaryotes contain both mitochondria and chloroplasts. Which sequence most likely describes the evolution of this group?
Ancestral anaerobic prokaryote engulfs heterotrophic prokaryote and then engulfs photosynthetic prokaryote.
Ancestral anaerobic prokaryote engulfs photosynthetic prokaryote and then engulfs heterotrophic prokaryote.
Both sequences are equally likely. 9

10. Trypanosoma, a kinetoplastid, is the causative agent of
HIV/AIDS
Malaria
Giardiasis
Trichomoniasis
Sleeping sickness
Answer: e

11. Trypanosoma, a kinetoplastid, is the causative agent of
HIV/AIDS
Malaria
Giardiasis
Trichomoniasis
Sleeping sickness

12. Which of the following was not formed by secondary endosymbiosis?
Dinoflagellates
Stamenophiles
Euglenids
Clorarachniophytes
Cyanobacteria
Answer: a

13. Which of the following was not formed by secondary endosymbiosis?
Dinoflagellates
Stamenophiles
Euglenids
Clorarachniophytes
Cyanobacteria

14. Which of the following most likely arose from endosymbiosis?
nuclear membrane and Golgi apparatus
ER and chloroplasts
chloroplasts and mitochondria
mitochondria and Golgi apparatus
Answer: c 14

15. Which of the following most likely arose from endosymbiosis?
nuclear membrane and Golgi apparatus
ER and chloroplasts
chloroplasts and mitochondria
mitochondria and Golgi apparatus 15

16. Scientific Skills Exercises
Cloned rRNA gene sequences for the six organisms were aligned and compared. The data table, called a comparison matrix, summarizes the comparison of 617 nucleotide positions from the gene sequences. Each value in the table is the percentage of the 617 nucleotide positions for which both organisms in the pair have the same composition. Any positions that were identical across the rRNA genes of all six organisms were omitted from this comparison matrix.

17. Find the cell that represents the comparison of Comamonastestosteroni and Escherichia coli. What value is given in that cell? 35 52 57 61
Answer: d

18. Find the cell that represents the comparison of Comamonastestosteroni and Escherichia coli. What value is given in that cell? 35 52 57 61

19. What does the value 61 signify about the comparable rRNA gene sequences in Comamonas testosteroni and Escherichia coli?
that 61% of the 617 nucleotide positions are different between the two species
that 61 nucleotides are different between the two species
that 61 nucleotides are the same in both species
that 61% of the 617 nucleotide positions are the same in both species
Answer: d

20. What does the value 61 signify about the comparable rRNA gene sequences in Comamonas testosteroni and Escherichia coli?
that 61% of the 617 nucleotide positions are different between the two species
that 61 nucleotides are different between the two species
that 61 nucleotides are the same in both species
that 61% of the 617 nucleotide positions are the same in both species

21. Why do some cells have a dash rather than a value?
Those cells would compare one species to itself.
Those cells would duplicate comparisons shown elsewhere in the matrix.
Those comparisons were not made by the researchers.
Answer: a

22. Why do some cells have a dash rather than a value?
Those cells would compare one species to itself.
Those cells would duplicate comparisons shown elsewhere in the matrix.
Those comparisons were not made by the researchers.

23. Why are some cells shaded gray, with no value?
Those cells would compare one species to itself.
Those cells would duplicate comparisons shown elsewhere in the matrix.
Those comparisons were not made by the researchers.
Answer: b

24. Why are some cells shaded gray, with no value?
Those cells would compare one species to itself.
Those cells would duplicate comparisons shown elsewhere in the matrix.
Those comparisons were not made by the researchers.

25. Why did the researchers choose only one plant (wheat) to include in the comparison matrix?
A comparison matrix with more than six species is too unwieldy.
Wheat is the plant that is most closely related to bacteria.
Only one source of mitochondrial rRNA was needed to represent all mitochondria.
Wheat is the only plant with mitochondrial rRNA genes.
Answer: c

26. Why did the researchers choose only one plant (wheat) to include in the comparison matrix?
A comparison matrix with more than six species is too unwieldy.
Wheat is the plant that is most closely related to bacteria.
Only one source of mitochondrial rRNA was needed to represent all mitochondria.
Wheat is the only plant with mitochondrial rRNA genes.

27. Why did the researchers include five bacterial species in the comparison matrix?
They wanted to identify which bacterium is most closely related to the ancestor of mitochondria.
They wanted to identify how many of the five bacterial species have rRNA genes.
One of the species was a test, and the other four were controls.
They wanted to identify the evolutionary relationships among the five bacterial species.
Answer: a

28. Why did the researchers include five bacterial species in the comparison matrix?
They wanted to identify which bacterium is most closely related to the ancestor of mitochondria.
They wanted to identify how many of the five bacterial species have rRNA genes.
One of the species was a test, and the other four were controls.
They wanted to identify the evolutionary relationships among the five bacterial species.

29. Which bacterial species has an rRNA gene that is most similar to that of the wheat mitochondrion?
M. capricolum
A. tumefaciens
E. coli
C. testosteroni
A. nidulans
Answer: b

30. Which bacterial species has an rRNA gene that is most similar to that of the wheat mitochondrion?
M. capricolum
A. tumefaciens
E. coli
C. testosteroni
A. nidulans

31. The rRNA gene of A. tumefaciens is most similar to the wheat mitochondrial rRNA gene. What does that suggest?
that the alpha proteobacteria are more closely related to the ancestor of mitochondria than the other bacterial taxa
that the beta proteobacteria are more closely related to wheat than the other bacterial taxa
that the alpha proteobacteria are more closely related to wheat than the other bacterial taxa
that the beta proteobacteria are more closely related to the ancestor of mitochondria than the other bacterial taxa
Answer: d

32. The rRNA gene of A. tumefaciens is most similar to the wheat mitochondrial rRNA gene. What does that suggest?
that the alpha proteobacteria are more closely related to the ancestor of mitochondria than the other bacterial taxa
that the beta proteobacteria are more closely related to wheat than the other bacterial taxa
that the alpha proteobacteria are more closely related to wheat than the other bacterial taxa
that the beta proteobacteria are more closely related to the ancestor of mitochondria than the other bacterial taxa